The port town of Ferrol has long been synonymous with Spanish national defense.

After the Spanish Navy built its arsenal and shipyards in Ferrol’s almost impregnable harbor in the 18th century, the city boomed. Naval engineers built elegant streets lined with glass balconies that became the envy of northwestern Spain, and more than a century later, Spain’s future dictator, Francisco Franco, the son of a naval officer, was born there.

Now the city, long since marred by industrial decay, unemployment and declining population, is becoming known for its warm welcome of Chinese industry into Spain and Western Europe.

In June SAIC Motor, one of China’s largest electronic vehicle manufacturers, chose a sleepy port just outside Ferrol as the site for a major plant. The project, which is expected to provide more than 1,000 jobs, has prompted widespread celebration across Ferrol.

That reflects a broader national consensus — even amid a rancorous election campaign in which politicians are sparring over other issues — over the need for Chinese investment.

The left-wing government of Pedro Sánchez is expected to sign off on the deal before the election on Nov. 29. If it doesn’t, a new conservative government is expected to. Either way, Ferrol will become the latest Spanish city to bet its economic future on hosting Chinese companies compatible with the country’s emphasis on green technology. Chinese battery makers, solar panel producers and other renewable energy companies are sprouting across Spain, where Chinese electric vehicle investments have grown faster over the past year than anywhere else in Europe.

The proposed plant in Ferrol embodies the trade-off between short-term economic opportunity and long-term risk that these Chinese investments present to Europe.

This summer, the Spanish news media reported that Spain’s security services were concerned that China might use the plant for espionage. The defense minister declined to comment on the reports, and the regional government quickly dismissed them as inaccurate.

What has lingered are deep questions about whether the increased Chinese presence, especially in one of Spain’s military heartlands, will eventually make Spain too reliant on Chinese supply chains, materials and technology, and make local Spanish firms more vulnerable to Chinese competition.